The Impact of Hybrid Fibers on Punching Shear Strength of Concrete Flat Plates Exposed to Fire

This study presents an investigation about the effect of fire flame on punching shear strength hybrid fiber reinforced concrete flat plates. The main considered parameters are type (steel or glass) and burning steady-state temperatures (500 600°C). A total 9 half-scale plate specimens dimensions 1500mm×1500mm×100mm 1.5% volume fraction were cast divided into 3 groups. Each group consisted that identical to those in other second third groups subjected influence for 1 hour temperature 500 600°C respectively. Regarding cooling process, water sprinkling was applied directly after stage represent sudden process. Generally, obtained results exhibited a significant increase capacity fiber-reinforced slabs as compared corresponding no even at elevated 600°C. ultimate load increased by 16.6, 19, 21.5% 25, 500, respectively, steel 13.9, 27.2, 34.6% containing two mixed types fibers glass), with reference specimen same In addition, indicated fibers' presence resulted gradually failure more ductile mode, whereas brittle mode did not contain fibers.